diff --git a/packages/angular/build/src/builders/library/builder-state.ts b/packages/angular/build/src/builders/library/builder-state.ts
index 9057ef41b815..5f55f5b2b915 100644
--- a/packages/angular/build/src/builders/library/builder-state.ts
+++ b/packages/angular/build/src/builders/library/builder-state.ts
@@ -256,10 +256,8 @@ export class BuilderState {
       return true;
     }
 
-    for (const file of this.#pendingCompilationFiles) {
-      if (this.#watchedCompilationFiles.has(file)) {
-        return true;
-      }
+    if (!this.#pendingCompilationFiles.isDisjointFrom(this.#watchedCompilationFiles)) {
+      return true;
     }
 
     this.#pendingCompilationFiles.clear();
@@ -281,12 +279,7 @@ export class BuilderState {
       return undefined;
     }
 
-    const files = new Set(modifiedFiles);
-    for (const file of this.#pendingCompilationFiles) {
-      files.add(file);
-    }
-
-    return files;
+    return modifiedFiles.union(this.#pendingCompilationFiles);
   }
 
   /**
@@ -380,7 +373,7 @@ export class BuilderState {
     collectedAssets: CollectedAssets,
     manifestFiles?: readonly OutputFile[],
   ): ReadonlySet<string> {
-    const filesToDelete = new Set<string>();
+    let filesToDelete = new Set<string>();
 
     if (this.#hasUpdatedBundles) {
       this.#hasUpdatedBundles = false;
@@ -394,21 +387,14 @@ export class BuilderState {
         }
       }
 
-      for (const prevFile of this.#emittedBundleFiles) {
-        if (!nextBundleFiles.has(prevFile)) {
-          filesToDelete.add(prevFile);
-        }
-      }
-
+      filesToDelete = this.#emittedBundleFiles.difference(nextBundleFiles);
       this.#emittedBundleFiles = nextBundleFiles;
     }
 
     if (manifestFiles) {
       const nextManifestFiles = new Set(manifestFiles.map((file) => file.path));
-      for (const prevFile of this.#emittedManifestFiles) {
-        if (!nextManifestFiles.has(prevFile)) {
-          filesToDelete.add(prevFile);
-        }
+      for (const prevFile of this.#emittedManifestFiles.difference(nextManifestFiles)) {
+        filesToDelete.add(prevFile);
       }
 
       this.#emittedManifestFiles = nextManifestFiles;
diff --git a/packages/angular/build/src/builders/library/pipeline/entry-points.ts b/packages/angular/build/src/builders/library/pipeline/entry-points.ts
index f932fb992fc6..8e4bda376326 100644
--- a/packages/angular/build/src/builders/library/pipeline/entry-points.ts
+++ b/packages/angular/build/src/builders/library/pipeline/entry-points.ts
@@ -308,10 +308,10 @@ export function collectEntryPointsToBundle(
     const previousBundleResult = previousBundleResults.get(entryPoint.name);
     const hasEsmChanges =
       !previousBundleResult ||
-      hasEntryPointChanges(previousBundleResult.esmModuleIds, pendingChangedEsmFiles);
+      !previousBundleResult.esmModuleIds.isDisjointFrom(pendingChangedEsmFiles);
     const hasDtsChanges =
       !previousBundleResult ||
-      hasEntryPointChanges(previousBundleResult.dtsModuleIds, pendingChangedDtsFiles);
+      !previousBundleResult.dtsModuleIds.isDisjointFrom(pendingChangedDtsFiles);
 
     if (hasEsmChanges || hasDtsChanges) {
       executionResult.addLog(`Compiling ${entryPoint.displayName}...`);
@@ -326,27 +326,3 @@ export function collectEntryPointsToBundle(
 
   return itemsToBundle;
 }
-
-/**
- * Checks whether any file in `changedFiles` belongs to the given entry point's `moduleIds`.
- *
- * @param moduleIds Set of virtual POSIX module IDs referenced by the entry point's previous bundle.
- * @param changedFiles Set of POSIX file paths that changed during compilation.
- * @returns `true` if at least one changed file is part of `moduleIds`; otherwise `false`.
- */
-function hasEntryPointChanges(
-  moduleIds: ReadonlySet<string>,
-  changedFiles: ReadonlySet<string>,
-): boolean {
-  if (changedFiles.size === 0) {
-    return false;
-  }
-
-  for (const file of changedFiles) {
-    if (moduleIds.has(file)) {
-      return true;
-    }
-  }
-
-  return false;
-}
diff --git a/packages/angular/build/src/tools/sass/rebasing-importer.ts b/packages/angular/build/src/tools/sass/rebasing-importer.ts
index 889d26ef567e..ccc5fa3c4664 100644
--- a/packages/angular/build/src/tools/sass/rebasing-importer.ts
+++ b/packages/angular/build/src/tools/sass/rebasing-importer.ts
@@ -209,8 +209,8 @@ export class RelativeUrlRebasingImporter extends UrlRebasingImporter {
       // If there is a preprocessed cache of the directory, perform an intersection of the potentials
       // and the directory files.
       const { files, directories } = cachedEntries;
-      foundDefaults = [...defaultPotentials].filter((potential) => files.has(potential));
-      foundImports = [...importPotentials].filter((potential) => files.has(potential));
+      foundDefaults = [...defaultPotentials.intersection(files)];
+      foundImports = [...importPotentials.intersection(files)];
       hasPotentialIndex = checkDirectory && !hasStyleExtension && directories.has(filename);
     } else {
       // If no preprocessed cache exists, get the entries from the file system and, while searching,
diff --git a/packages/angular_devkit/core/src/json/schema/utility.ts b/packages/angular_devkit/core/src/json/schema/utility.ts
index e23f5fad9cbe..83bc336e0952 100644
--- a/packages/angular_devkit/core/src/json/schema/utility.ts
+++ b/packages/angular_devkit/core/src/json/schema/utility.ts
@@ -53,7 +53,7 @@ export function getTypesOfSchema(schema: JsonSchema): Set<string> {
 
   if (isJsonObject(schema.not)) {
     const notTypes = getTypesOfSchema(schema.not);
-    potentials = new Set([...potentials].filter((p) => !notTypes.has(p)));
+    potentials = potentials.difference(notTypes);
   }
 
   if (Array.isArray(schema.allOf)) {
@@ -67,7 +67,7 @@ export function getTypesOfSchema(schema: JsonSchema): Set<string> {
     let options = new Set<string>();
     for (const sub of schema.oneOf) {
       const types = getTypesOfSchema(sub as JsonObject);
-      options = new Set([...options, ...types]);
+      options = options.union(types);
     }
     potentials = new Set([...options].filter((o) => potentials.has(o)));
   }
@@ -76,7 +76,7 @@ export function getTypesOfSchema(schema: JsonSchema): Set<string> {
     let options = new Set<string>();
     for (const sub of schema.anyOf) {
       const types = getTypesOfSchema(sub as JsonObject);
-      options = new Set([...options, ...types]);
+      options = options.union(types);
     }
     potentials = new Set([...options].filter((o) => potentials.has(o)));
   }
diff --git a/packages/angular_devkit/core/src/utils/partially-ordered-set.ts b/packages/angular_devkit/core/src/utils/partially-ordered-set.ts
index 21e3fb5c5410..258b6138f66f 100644
--- a/packages/angular_devkit/core/src/utils/partially-ordered-set.ts
+++ b/packages/angular_devkit/core/src/utils/partially-ordered-set.ts
@@ -84,23 +84,7 @@ export class PartiallyOrderedSet<T> {
       const itemDeps = this._items.get(item) || new Set<T>();
 
       // If the dependency list is equal, just return, otherwise remove and keep going.
-      let equal = true;
-      for (const dep of deps) {
-        if (!itemDeps.has(dep)) {
-          equal = false;
-          break;
-        }
-      }
-      if (equal) {
-        for (const dep of itemDeps) {
-          if (!deps.has(dep)) {
-            equal = false;
-            break;
-          }
-        }
-      }
-
-      if (equal) {
+      if (deps.size === itemDeps.size && deps.isSubsetOf(itemDeps)) {
         return this;
       } else {
         this._items.delete(item);
@@ -108,10 +92,8 @@ export class PartiallyOrderedSet<T> {
     }
 
     // Verify all dependencies are part of the Set.
-    for (const dep of deps) {
-      if (!this._items.has(dep)) {
-        throw new DependencyNotFoundException();
-      }
+    if (!deps.isSubsetOf(this._items)) {
+      throw new DependencyNotFoundException();
     }
 
     // Verify there's no dependency cycle.